The Northern Italian Peninsula had been a battleground between Hungary, Austria, France and the terrenal interests of the Papacy. Composed by many principalities and republics with allegiance to one or other power.
After three Franco-Austrian wars between 1795 and 1828, France and Hungary claimed most northern Italy, but this lead to a strong national sentiment between the Italians, and a general uprising against France, Hungary and the Papacy arouse in 1830. This rebellion was supported by Austria, Bavaria, Helvetia, and Aragon. In August 1830, Italy was proclaimed as a new Kingdom.
Hungary recognized Italy in 1840, while France did it in 1842. Rome did not recognized the Kingdom of Italy until 1962.
In 1914 Lombardy seceded from Italy.